The assignee ranking for this dataset covers 12 companies, and one leads clearly with 23 records against a fifth-place figure of 7 and a tenth-place figure of 2. That gap indicates a single company has built the deepest portfolio in this space, making it the first stop for any freedom-to-operate review. The ranking is the complete list the data endpoint returns for this search, not a curated top-50 or top-100 cut, so smaller players genuinely file less here rather than being excluded by a cutoff.

Based on the complete years in this dataset, filing has declined: 2017 was the peak year at 16 records, and the dataset’s own comparison shows 2021’s 12 filings falling to 0 by 2024, a -100% change over that span. However, 2025 and 2026 figures should not be read as confirming further decline, because publication typically lags filing by around 18 months and recent years are still filling in. A fair read is that the field cooled after an initial wave of filing rather than that it is currently collapsing.

Claims concentrate heavily in container and packaging structure (B65D, 81.3% of the 75 records) and refrigeration or cooling apparatus (F25D, 61.3%), with layered materials such as vacuum insulated panel laminates (B32B) a distant third at 29.3%. Smaller classes like heat-exchange apparatus, pipe fittings and carton-making each appear in only a handful of records. This tells you where claim language is dense — container geometry and thermal insulation — and where it is comparatively thin.